A Holter monitor records your heart’s electrical activity continuously for 24–48 hours (or longer) while you go about daily activities. It detects rhythm problems—atrial fibrillation, pauses, tachycardia, premature beats—shows heart rate trends, frequency and timing of abnormal events, and helps correlate symptoms (dizziness, palpitations, fainting) with ECG changes. It can also assess medication or pacemaker effectiveness.

Costs vary by country and provider. In India a 24‑hour Holter typically costs about ₹500–₹3,000 (~$6–$40). In the US out‑of‑pocket prices commonly range $100–$700 (often $200–$500), though insurance may cover most. In the UK it’s free on the NHS; private clinics charge roughly £80–£250. Final price depends on facility and reporting fees.

No — a Holter monitor records continuous heart rhythm to detect arrhythmias and can sometimes show signs of ischemia (transient ST-segment changes), but it cannot directly diagnose coronary artery blockages. To evaluate blockages, clinicians use stress tests, cardiac enzymes, CT coronary angiography or invasive coronary angiography. If symptoms or suspicious Holter findings occur, see a cardiologist for definitive testing.

A Holter test continuously records heart electrical activity over 24–48 hours, detecting intermittent arrhythmias and episodes an ECG might miss. Benefits include correlating symptoms (palpitations, dizziness, syncope) with rhythm changes, evaluating treatment or pacemaker effectiveness, identifying silent ischemia or atrial fibrillation, measuring heart rate variability, and guiding diagnosis and management noninvasively during normal daily activities.

Side effects of a Holter monitor are usually minor: skin irritation, redness, itching, or small blisters from adhesive electrodes; discomfort or soreness from leads and the recorder strap; mild sleep disturbance or activity restriction (no showering or swimming while wearing it); and anxiety about the device. Rarely, allergic reactions to adhesives or occasional skin abrasions occur. There are no systemic side effects.

A Holter monitor is usually worn continuously for 24–48 hours (sometimes 72 hours or up to 1–2 weeks with extended patch monitors). Device hookup takes about 10–30 minutes and removal is quick. You can continue normal activities while wearing it. The actual recording period is the 24–48 hours, and formal analysis of the data typically takes a few days for clinician review.